Instead of being able to jump into the game and start adventuring, some were given a "You're Too Early" message and refused entry into the closed beta.
We'll be diving into the beta as soon as it goes live, so be sure to check back with us for more coverage on Rare's latest title, Sea of Thieves.
"We're aware of these issues and are working quickly to address and deal with them!" the Sea of Thieves wrote in a separate tweet responding to one fan's frustrations.
Rare acknowledged the error on Twitter, saying the team is "fully focussed on a resolution". However, it appears many pre-purchasers are being met with a "too early" error message when they attempt to launch the beta.
"We're still investigating ongoing issues with launching the Closed Beta", reads a tweet from the official Sea of Thieves account.
The competition opened alongside the closed beta which kicked off today and will close at the same time as it. Rather than featuring a portion of the full game, Rare says it crafted a tailored experience for the beta "that offers a true taste of the pirate life".